a. Good evening, and thanks for joining us. With the winter olympics fast approa approaching, there is a substantial potential for a terrorist attack at the sochi games. So how did a Russian beach side resort become the site for the games in the first place? Tonight a whistleblower with a price on his head makes startling allegation about shady deals to ABC's chief investigative correspondent Brian Ross in our exclusive "Olympic gold olympic greed." Reporter: This year's winter olympics could have been held in the Austrian alps with its storied villages. Or in this popular ski resort, a snowboarder's paradise. Instead, the international olympic committee chose a subtropical Russian city on the black sea, famed for its summer beaches, but one of the few places in Russia that rarely gets snow. And that's the least of this city's problems. While sochi is known for its palm tree ins stoefd snow, there's a blizzard of allegations of unsavory ties to organized crime figures, official corruption and islamic terrorists who have threatened to attack here. All of which raises the question why the international olympic committee chose sochi in the first place. Has olympic greed become more important than olympic gold? To find out, we met some of the few Russian journalists brave enough to ask those questions. Including sergei kanov who always has a hidden camera in his bag in case he is attacked again, as he has been twice before. One put a slip knot over my net and tried to strangle me. And a Russian businessman who went into hiding after allegations of corruption that led to threats on his life. You will be drowned in blood. Reporter: And we heard from the mayor of sochi who tried to laugh off our questions about corruption and mafia tie with an aide offcamera telling him not to answer. What are you talking about? Never. Sochi could never be a mafia city because this is a city where people come to relax. Reporter: The decision by the international olympic committee to choose sochi was made seven years ago. There's no doubt that the personal appearance by Russian president Vladimir Putin was a big factor. He spoke in English, something he almost never does in public. Sochi's olympic bid has already brought its benefits. Reporter: But that's not the whole story of why Putin and the Russians won the day. Awarded to the city of sochi. Reporter: An ABC news investigation found that behind the scenes, this mystery man was directly involved in helping Russia get the needed olympic votes. He says he's just a businessman, a vice president of what's known as the olympic council of Asia. He has been publicly thanked by the Russian olympic committee for his single minded work in delivering the votes of some asian countries for sochi, without which it would have been hard for sochi to count on the victory. But we discovered he is much more than just another businessman with friends on the olympic committee. He is one of the four or five most important people in the heroin trade in the world. He's absolutely a major and very dangerous gangster. Reporter: Craig Murray, the former british ambassador to Uzbekistan says he has a track record of payoffs to government officials to make sure his drugs move across Asia and Russia into Europe without interference. A lot of it ends up in the United Kingdom. A lot is used for the european market. A lot is used in the Russian market. St. Petersburg itself has a heroin problem. The U.S. Described him as a key member of a huge Russian asian syndicate with drugs in the countries of central Asia that travel all the way to Europe. Yet that's the very person the Russians admit they used to help them get the votes for winter olympics in sochi. . Translator: If we're talking about these links between the criminals and the kremlin, you don't have to go far. Reporter: This Russian investigative reporter showed us photos with rahimov with the mafia boss of sochi before he was killed last yeern was told he would not help Russia unless there was something in it for him and his close-knit criminal network, which is known in Russia as the thieves in law. Translator: There was obviously some sort of agreement between the kremlin and the thiefs in law. And he showed us this photo of rahimov a at a Russian olympic children events. His ties to heroin trafficking apparently not a problem. Translator: At that time, he was known as a drug trafficker and there was a warrant for his Arre arrest in Uzbekistan. Reporter: Rahimov confirmed to ABC news his role in helping Russia get the olympics. Quote, he talked to them, the translator said. He convinced them because of his good relations with these people. He has great influence. He added it was not necessary to pay any money or bribes. The olympic committee should be embarrassed by this, but let's face it, this is one of -- it's a terrible scandal. But it's one of a large number of scandals that have dogged sbefr national sports for many years. And it seems impossible to embarrass these people into behaving well. Reporter: A cloud of crime and corruption has lingered over the sochi olympics ever since. As Russia went on an estimated $50 billion to $60 billion spending spree for winter games with dozens of facilities and buildings springing up all across the area as seen in these time lapse promotional videos. Critics say huge amounts of that money ended up in the bank accounts of well connected Russians. Everyone knows this is the most criminal case in the history of Russia. A former Russian deputy prime minister and Putin political rival has produced what he says is documented evidence of ram pid criminality in the most expensive olympics ever. They stole $30 billion all together. They stole $30 billion? Yeah. It's about half of the cost. He points to the olympic stadium, three times the cost of any previous stadium anywhere in the world. The $9 billion highway and railroad that had to be used to link the resort cities to where the snow is, 30 miles away. By most accounts, this may be the world's most expensive highway per mile. About $300 million a mile. It's the corruption, not the concrete, that makes it so very expensive. For example, American program to fly to Mars is three times cheaper. Did you know that? This is $3 billion. Reporter: And then there's the olympic ski jump, two years behind schedule and more than six times over budget. This remarkable video shows president Putin's reaction as aides try to dodge around the question of who is responsible. It was a top Russian olympic official. Who was that? Translator: What's he doing now? Translator: He's managing resorts in the northern caucuses. Reporter: Putin is not satisfied. Reporter: What else? Reporter: I don't know what else he has been doing. Reporter: Now he asks the other aide. Translator: He's the vice president of the olympic committee. So the vice president of the national olympic committee is taking care of such a large construction. Reporter: Putin's steely reaction says it all. The olympic vice president has now fled the country, accused of embezzling several million dollars, a charge he denies. Despite all that, in an interview with George stephanopolous, president Putin said no one had presented any evidence of a serious corruption problem. We have not seen any big large scale instances of corruption in connection with the implementation of the sochi olympics project. And we heard the same thing from the mayor of sochi who gave us a 45-minute walking tour of all the improvements he says the city is making. Telling us reports of corruption are just journalists' fantasies. So you don't think this is going to be a corrupt olympics? Translator: I can say with certainty there were no corruption schemes during the construction of the olympic facilities. Reporter: But the evidence of corruption and criminality is overwhelming right up to the president in Moscow, to the officials who control construction contracts in sochi 37. Morisov now in exile in Britain after going public with his allegations said he did business with tough officials in the president's office. You have to pay, there is no way out. He says he used pieces of luggage like this to deliver tens of millions of ruble, what he called a corruption tax, to a key official. Stuffed with rubles? Stuffed with rubles. And I've given this a few times. Reporter: Who got all that money? You know that this is not my money. This is not money for me. I am to bring it upstairs. Reporter: He said a prosecutor's report concluded the official personally seched the bribe in the form of a large sum of money but no charges were brought. And now morisov says he is a marked man, even living in an undisclosed location far away from Russia in England. T fearing the threats against him will be carried out once the olympics are over. What were the threats against you? You will be drowned in blood. You will wash with blood. Those are the -- Reporter: You'll be drowned in blood. The international olympic committee says all the allegations in our report should be handled by the host government, president Putin's Russia. And as Putin told ABC news, the Russians have already determined there is no serious corruption problem surrounding the olympics. See no evil, hear no evil.

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